Modifying optical properties of thin film structures using an absorbing element

Patent metadata

Field	Value
Publication number	US-10539727-B2
Application number	US-201615757339-A
Country	US
Kind code	B2
Filing date	Sep 6, 2016
Priority date	Sep 4, 2015
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

A method of making a multi-layered film includes depositing thin film layers onto a first side of a double-sided transparent substrate. The thin film layers are transparent, and two adjacent layers of said plurality of thin film layers have different refractive indices. One or more absorbers are deposited at an interface formed between two of the thin film layers that are adjacent to one another, or formed by the first side of the substrate and one of the thin film layers. The absorbers absorb selected wavelengths of incident light and reflect part of the incident light after inducing a phase shift. The location of the interface is selected to provide desired wavelengths of absorbed and reflected light. The multi-layered film has a first appearance when viewed from the first side of the substrate and a second appearance when viewed from the second side of the substrate.

First claim

What is claimed is:

1. A method of making a multi-layered film comprising:
providing a transparent substrate having a first side and a second side;
depositing a plurality of thin film layers on the first side of the substrate;
wherein the plurality of the thin film layers are transparent and two adjacent layers of said plurality of thin film layers have different refractive indices, and
wherein each layer of the plurality of thin film layers has a thickness of less than 800 nanometers;

depositing a plurality of absorbing elements at an interface formed between two adjacent layers of said plurality of thin film layers or formed by the first side of the substrate and a layer of said plurality of thin film layers;
wherein the absorbing elements absorb selected wavelengths of incident light and reflect part of the incident light after inducing a phase shift;
wherein the location of the interface where the plurality of absorbing elements are deposited is selected to provide desired wavelengths of absorbed and reflected light;
wherein the multi-layered film has a first appearance when viewed from the first side of the substrate and a second appearance when viewed from the second side of the substrate;
wherein the first appearance comprises a first reflected color and the second appearance comprises a second reflected color; and
wherein the first reflected color is different from the second reflected color.

2. The method of claim 1 , wherein the wavelengths of light absorbed and the phase shift are dependent on the number and thickness of layers in the plurality of thin film layers.

3. The method of claim 1 , wherein the substrate is made of glass, quartz, metal oxides, mixed transition metal oxides, metal nitrides, or polymers.

4. The method of claim 1 , wherein the substrate is made of silicon oxide, antimony tin oxide, zinc oxide, aluminum doped zinc oxide, vanadium oxide, titanium oxide, tin oxide, indium tin oxide, polyethylene, polypropylene, polycarbonate, polymethylmethacrylate, cellulose acetate butyrate, polyethylene terephthalate, polyvinyl chloride, polysulfone, polysaccharides, or proteins.

5. The method of claim 1 , wherein the plurality of thin film layers comprises glass, quartz, metal oxides, mixed transition metal oxides, metal nitrides, polymers, dielectric nanoparticles, or composites of polymers with nanoparticles fillers.

6. The method of claim 1 , wherein the plurality of thin film layers comprises silicon oxide, antimony tin oxide, zinc oxide, aluminum doped zinc oxide, vanadium oxide titanium oxide, tin oxide, indium tin oxide, polyethylene, polypropylene, polycarbonate, polymethylmethacrylate, cellulose acetate butyrate, polyethylene terephthalate, polyvinyl chloride, polysulfone, polysaccharides, proteins, dielectric nanoparticles, or composites of polymers with nanoparticles fillers.

7. The method of claim 1 , wherein the plurality of absorbing elements comprises a transition metal, a transition metal complex, a metal alloy, a metalloid, a metal oxide, a metal nitride, a metal sulfide, or a molecular absorber.

8. The method of claim 7 , wherein the plurality of absorbing elements comprises nanoparticles.

9. The method of claim 1 , wherein the plurality of absorbing elements are spherical, cylindrical, oblong, prismatic, ellipsoidal, disc, irregular, or acicular in shape.

10. The method of claim 1 , wherein each absorbing element of the plurality of absorbing elements comprises an interior core and an exterior shell and the material of the interior core and the exterior shell are different.

11. The method of claim 1 , wherein each absorbing element of the plurality of absorbing elements comprises a stack of concentric shells, wherein the stack of concentric shells comprises a plurality of adjacent layers with the adjacent layers made of a first material and a second material, wherein the first material and the second material are different.

12. The method of claim 1 , wherein one or more of the plurality of thin film layers have a refractive index of about 1.9.

13. The method of claim 1 , wherein the plurality of absorbing elements comprises a thin film.

14. The method of claim 1 , wherein the plurality of absorbing elements is deposited first on the transparent substrate followed by the deposition of the plurality of thin film layers above the plurality of absorbing elements.

15. The method of claim 14 , wherein the plurality of absorbing elements is treated with a coupling agent to improve adhesion with the transparent substrate or the interface.

16. The method of claim 14 , wherein the interface is treated with a coupling agent to improve adhesion with the absorbing elements.

17. A multi-layered film comprising:
a transparent substrate having a first side and a second side;
a plurality of distinct thin film layers on the first side of the substrate;
wherein the plurality of the thin film layers are transparent and the adjacent distinct thin film layers have different refractive indices, and
wherein each layer of the plurality of thin film layers has a thickness of less than 800 nanometers;

a plurality of absorbing elements having plasmon resonance at an interface formed between two adjacent layers of said plurality of thin film layers or formed by the first side of the substrate and a layer of said plurality of thin film layers;
wherein the plurality of absorbing elements forms a patterned film;
wherein the plurality of absorbing elements absorbs selected wavelengths of incident light and reflect part of the incident light after inducing a phase shift;
wherein the location of the interface where the plurality of absorbing elements is deposited is selected to provide desired wavelengths of absorbed and reflected light;
wherein the multi-layered film has a first appearance when viewed from the first side of the substrate and a second appearance when viewed from the second side of the substrate;
wherein the first appearance comprises a first reflected color and the second appearance comprises a second reflected color; and
wherein the first reflected color is different from the second reflected color.

18. The multi-layered film of claim 17 , wherein the plurality of absorbing elements forms an irregular array.

19. The multi-layered film of claim 17 , wherein the plurality of absorbing elements forms a regular array.

20. The method of claim 1 , wherein the plurality of absorbing elements have plasmon resonance.

Assignees

• Harvard College

Inventors

• England Grant
• Russell Calvin
• Kay Theresa
• Shirman Elijah
• Burgess Ian
• Vogel Nicolas
• Aizenberg Joanna

Classifications

• B41M3/148

  Transitory images, i.e. images only visible from certain viewing angles · CPC title

• G02B5/285 Primary

  comprising deposited thin solid films (G02B5/281 - G02B5/289 take precedence; multilayered film filters for fibre optic multiplexing G02B6/29361) · CPC title

• B44F1/066

  comprising at least two transparent elements, e.g. sheets, layers (layered products of glass and synthetic resin containing decorations or patterns B32B17/10247; window units comprising two or more parallel glass panes E06B3/66) · CPC title

• B44F1/08

  characterised by colour effects · CPC title

• B42D25/373

  Metallic materials · CPC title